1. Field Of The Invention
The present invention relates to locking devices for securing marine drive units with through propeller hub exhaust. The locking device locks the propeller to the foot/lower unit of the marine drive unit and provides a point where the user can secure the unit via chain or cable to a stationary object.
2. General Background
There are several locking devices on the market that lock different aspects of the trailable type power boat. There are locking devices for the trailer, locking devices for the outboard motor, locking devices for inboard/outboard drive units, and locking devices specifically for the propeller.
Currently there is not a locking device or locking system available that can lock all the major components. Using individual locking devices for each of the above listed components is expensive and time consuming. Trailer tongue type locks are available which lock the tongue of the trailer so that the trailer cannot be connected to a ball on an auto trailer hitch. These locks suffer in that they do not prevent a thief from simply tying the trailer tongue to a truck or auto bumper, using rope, and driving away. Several devices have been patented which relate generally to outboard motor lock systems. Some of these lock systems specifically address the boat propeller. Examples include U.S. Pat. No. 3,732,033 entitled "Boat Propeller Lock". The '033 patent provides an enclosure which can be locked in position to conceal a nut used to secure a boat propeller to a drive shaft. The enclosure includes a cover portion that can be locked into engagement with a base portion that is retained by and specifically the nut. Both the enclosure and the lock mechanism therefore are formed of an oxidation resistant material so as to prevent deterioration during use in the water environment.
U.S. Pat. No. 3,981,165 entitled "Outboard Motor Propeller Lock System" provides a device that is comprised of an inner thin lock and an outer thin lock, with the outer thin lock adapted to lock to the interior thin lock to prevent removal of its locking position on a propeller housing.
The Reese patent U.S. Pat. No. 3,759,076 entitled "Marine Propeller Lock" provides an elongated bar apparatus for lengthwise insertion longitudinally between the inner and outer sleeve portions of a marine propeller. The bar includes hook structure on the end to be inserted between the sleeve portions for hooked engagement with one of the generally radial lugs supporting the outer sleeve portion from the inner sleeve portion and a slide member is mounted on the other end portion of the rod and includes a laterally offset portion defining a recess opening toward the hooked end of the rod. The slide member is slidable along the rod into position to overlie and telescopingly receive an associated propeller retaining nut in the recess defined by the offset portion and a lock assembly is provided for releasably locking the slide member in position against movement away from the hooked end of the rod whereby access to the propeller retaining nut by a wrench or other nut removing tool is prevented and unauthorized removal of the propeller from the associated propeller shaft is prevented. As a safety measure, the propeller lock is free of portions which would interfere with normal turning of the associated propeller and thus inadvertent operation of the associated motor without first removing the propeller lock will not cause damage to the propeller or other associated running gear even though a turning propeller having the propeller lock mounted thereon will cause an apparent vibration so as to immediately remind a person who has inadvertently started the associated motor that the propeller lock has not been removed.
Another hub lock for marine propellers is seen in the Milewicz U.S. Pat. No. 3,981,617 entitled "Marine Propeller Lock".
An enclosure for locking a boat propeller is seen in the Sims patent U.S. Pat. No. 4,257,247 entitled "Boat Propeller Security Device". The apparatus includes a cover having legs which extend from the rear of the propeller and in between each of the propeller blades. The legs provide openings at their end portions making it possible for attaching a chain through the feet and securing opposite ends of the chain with a lock.
An enclosure device for use with a marine inboard/outboard type outdrive unit is seen in the Peters U.S. Pat. No. 4,325,701 entitled "Protective Device". The device of the '701 patent provides a housing having a top wall, a back wall, and opposing side walls which extend downwardly from the top wall and on opposite sides thereof. The top wall of the housing includes a slot through the mooring eye on the outdrive is positioned and in so doing the threaded fasteners which connect the outdrive to the transmission are inaccessibly positioned between the housing side walls. The housing itself is removably secured to the outdrive by a padlock having its bolt extending through the mooring eye in order to permit removal of the outdrive only by authorized personnel.
The Brushaber U.S. Pat. No. 4,736,603 entitled "Marine Drive Unit Anti-Theft Device" provides an anti-theft device for a marine drive unit which includes a cupped member for location around a threaded fastener which secures the drive unit in place so as to enable a blocking device to be secured in position to block access to the threaded fastener and thereby preclude unauthorized removal of the threaded fastener and the drive unit, the cupped member having outer surfaces lying in mutually perpendicular planes forming a corner complementary to a corner of the drive unit to preclude rotation of the cupped member when seated in the corner of the drive unit in order to further prevent unauthorized rotation of the threaded fastener.
The Evans U.S. Pat. No. 4,760,719 entitled "Non-Key Locking Cable Lock For Marine Vessel" provides a cable-like device for securing an outboard motor to a marine vessel. A portion of the steel cable extends into the transom of the boat.
All of the current patents and devices on the market that are propeller locking systems prevent access in one form or another to the propeller attachment nut. This device differs in that the propeller attachment nut is accessible but the propeller itself is constrained where that it cannot be slid off the propeller shaft.